Not likely to be seen each year. The interior distance from the roof to the floor of the nestbox. Habitat dominated by trees.
Beak or mandible upper and lower. Sometimes called a Squirrel tooth-bender or hole protector.
Extension of the bill onto the forehead. States may have their own definitions. An unattached adult not paired that may challenge a breeding bird for a nest site. Early sacs may be eaten by parents for extra nutrition as the very young nestlings can not completely digest their food.
Long, stiff, specialized feathers that have sensory and protective functions. Young birds are said to have "fledged" when they have completely acquired their first true feathers and have left the nest. The source of much CBC data. A blanket of fur or "cotton" used to conceal eggs from predators or keep them warm when the female leaves the nest.
Area occupied and defended during nonbreeding season vs. A live House Sparrow used inside a ground trap to attract other House Sparrows. Sperm are transferred when the male briefly touches his swollen, sperm-containing cloaca to the cloaca of a receptive female. Tough, stiff but bendable wire mesh that comes in a roll.
The feathers along the front of the body, from the neck down.
Generally shorter and simpler than songs. If they want to get out of the chamber, they have to enter the trap.
Merging of sperm and ova. May indicate that they should be treated as a single species. Seen occasionally, but not regularly occurring in a region. The act of leaving the nest.
A feeder with metal or wooden dowels looks like prison cell bars on the sides to allow entry only to smaller birds. Used to grasp food and cling. Irrupt or irruption invasion: When more eggs are produced than can be raised, and there is not enough food for all, later hatching young or runt s, which are weaker and smaller than nestmates, starve or are neglected or are attacked by siblings siblicide.
Highly developed in seed-eating birds. Aerial version of the wing-spreading or wing-threat display, where a bird e. Primarily by male during pair formation, or in aggressive context. Drip edge or Rain groove: Less muscular in birds that eat softer foods like insects or fruit.
They have a dark-colored shaft, as opposed to the white or clear shaft of a mature feather.
Bill snapping or Beak clicking: Non-parental adults, called extra-pair helpers, auxiliaries or supernumeraries, usually do not breed themselves. It enables ornithologists to sort across taxa, and looks at primitive and derived characters.
Back part of the crown. Egg bound is a reasonably common, and potentially serious, condition that can lead to infection or damage to internal tissue.
Diurnal birds may still migrate at night. For a pair bonded bird e. Shining a light through an egg to see whether it is developing or not. Annual bird monitoring program done in late December and early January.General information on how to attract nesting bluebirds, including distinguishing nests and eggs of other cavity nesters, heat, dealing with house sparrows, data on bluebird trail.Download